Okay so upgraded via Kies to 4.3 last night. No major problems noticed as yet everything seems fine. Hate the draggable widget box on the lockscreen but thats my only gripe really. My question is i've seen a few comments that after a firmware upgrade a reset is best to clean up etc. Is this neccessary? Would i lose wifi passwords, apps etc and have to re do? How do i perform the correct reset if this is needed? I'm all for keeping things clean if needed.